The area of flavins and flavoproteins is a broad, but clearly and simply defined one. It covers all aspects of work pertaining to the chemistry and biology of compounds based on the isoalloxazine nucleus and on a very few closely related structures. Because of the extraordinary and perhaps unique versatility of flavin as a prosthetic group and its involvement in a variety of important biological oxidation and reduction processes, this area continues to expand rapidly. Interest in flavins ranges from theoretical chemistry to medical aspects. The 10th International Symposium is to be held in Como, Italy in 1990, as one of a series which have been organized at 3-year intervals since 1965. The last symposium was held in Atlanta at Emory University in 1987. Because of the continued and increasing pace of research in this area, it is important that regularly schedule meetings be held. Review lectures will cover the entire field and the meeting should bring together scientists from all over the world from a wide variety of disciplines, and promote valuable discussion and exchange of information. In addition, it should serve the purposes of keeping existing workers fully up-to-date with all aspects of the subject and of initiating young investigators into this important area of research.